全文获取类型
收费全文 | 132篇 |
免费 | 3篇 |
专业分类
化学工业 | 28篇 |
金属工艺 | 40篇 |
能源动力 | 1篇 |
轻工业 | 3篇 |
一般工业技术 | 17篇 |
冶金工业 | 43篇 |
原子能技术 | 3篇 |
出版年
2020年 | 1篇 |
2018年 | 12篇 |
2017年 | 11篇 |
2016年 | 5篇 |
2015年 | 4篇 |
2014年 | 6篇 |
2013年 | 8篇 |
2012年 | 10篇 |
2011年 | 8篇 |
2010年 | 5篇 |
2009年 | 7篇 |
2008年 | 3篇 |
2007年 | 5篇 |
2006年 | 3篇 |
2005年 | 1篇 |
2004年 | 5篇 |
2003年 | 2篇 |
2002年 | 2篇 |
2000年 | 2篇 |
1999年 | 3篇 |
1998年 | 8篇 |
1997年 | 1篇 |
1996年 | 3篇 |
1995年 | 2篇 |
1994年 | 4篇 |
1993年 | 3篇 |
1992年 | 2篇 |
1987年 | 2篇 |
1986年 | 1篇 |
1983年 | 1篇 |
1982年 | 1篇 |
1981年 | 2篇 |
1979年 | 1篇 |
1976年 | 1篇 |
排序方式: 共有135条查询结果,搜索用时 0 毫秒
21.
Activated tungsten inert gas (A-TIG) and flux-cored arc (FCA) weld metals were prepared using 304LN stainless steel plate. The weld metals were thermally aged at 923, 973 and 1023?K for 100?h to study the decomposition of initial δ-ferrite in A-TIG (~10 ferrite number (FN)) and FCA (~5 FN) weld metals into secondary phases like M23C6 carbides, χ and σ. Ferrite number is the measurement of δ-ferrite based on the principle of magnetic property using ferritescope. Preliminary microstructural studies revealed the formation of carbides in FCA weld metals aged at 923?K for 100?h, which was correlated with higher carbon content (0.04?wt-%), and also ageing at higher temperature transformed δ-ferrite into χ/σ phases. However, A-TIG weld metals showed the transformation of δ-ferrite mainly into χ/σ phases. The δ-ferrite transformation kinetics was found to be sluggish in A-TIG weld metals compared to FCA weld metals. This difference was attributed to the difference in the carbon contents of A-TIG and FCA welds. Activated tungsten inert gas weld metals showed better uniform and pitting corrosion resistance compared to FCA weld metals in as-deposited and thermally aged conditions. Presence of higher amount of initial δ-ferrite content in A-TIG weld metal helped diffusion of minor alloying elements like sulphur and phosphorous into it, thereby reducing their microsegregation at the δ/γ interface boundaries and subsequent pitting corrosion attack. Thus, A-TIG welding process was found to be superior compared to FCA welding process. 相似文献
22.
A. Ravi Shankar U. Kamachi Mudali Vipin Chawla Ramesh Chandra 《Ceramics International》2013,39(5):5175-5184
Hafnium nitride (HfN) is a refractory compound considered to be a suitable material for reaction barriers. The present paper deals with the preparation of HfN thin films by reactive magnetron sputtering on high density (HD) graphite and niobium substrates. Deposition process parameters have been optimised with Si(100) substrate in order to get HfN coating of 3 μm thickness. The optimised parameters were used to deposit HfN on HD graphite and on niobium substrates. The results showed that HfN coating with a thickness of 2.8 μm was successfully deposited on HD graphite and niobium substrates. The presence of HfN was confirmed by glancing incidence X-ray diffraction (GIXRD) and X-ray photoelectron spectroscopy (XPS). XRD studies on HfN coating on Si(100), HD graphite and Nb substrates showed nanocrystalline grains of size 130, 55 and 46 Å, respectively. The surface morphology of HfN coating on HD graphite and niobium by atomic force microscope (AFM) and scanning electron microscope (SEM) showed that nanoparticles are getting agglomerated into clusters. The HfN coating on niobium substrate exhibited good adhesion compared to that on HD graphite as studied by microscratch test. The thermal stress generated in the sputter deposited HfN coating on HD graphite and niobium substrates were calculated by analytical formula for thermal stress. The tensile and highly compressive stresses observed in the HfN coating on niobium and HD graphite, respectively, indicated a lower adhesive strength of the coating on the later than that of the former. 相似文献
23.
A peculiar type of pin prick spots/dents on the surface of some galvannealed sheets was observed, causing significant appearance problems in the finished product. In the present study, the surface defect was characterized by visual inspection, optical microscopy, microhardness, scanning electron microscopy and EDX to understand the source and mechanism of the defects. In the visual inspection, these peculiar defects were found to align in one direction. The SEM examination exhibited three distinct regions of the surface defect apart from the matrix: (1) particle, (2) a dense layer surrounding the particle, and (3) a crater region surrounding the particle. The EDX analysis of these regions indicated enrichment of Al and Fe and depletion of Zn in the particle. The microhardness measurements of the dense layer and the matrix indicated an increase in hardness in the dense layer compared to the matrix. Based on the preliminary results, the following hypothesis was made: Dross/zinc dust falling from snout wall or intermetallic phase or reaction product particles embed in the craters on the strip surface; during subsequent skin-pass rolling these particles peel out the zinc coating in the craters, thus densifying and flattening the region surrounding the particle. The paper presents the results of the investigation. 相似文献
24.
Pradeep Kumar Samantaroy Girija Suresh Nanda Gopala Krishna U. Kamachi Mudali 《Journal of Materials Engineering and Performance》2013,22(4):1041-1053
Nickel-based alloys are being considered as candidate materials for the storage of high level waste. In the present investigation, Alloy 600 was assessed by potentiodynamic anodic polarization technique for its corrosion behavior in the as-received, solution annealed, and sensitized condition in 3 M HNO3 and 3 M HNO3 containing simulated high level waste. From the results of the investigation, it was found that the solution annealed specimen possesses superior corrosion resistance compared to the as-received and sensitized specimen. Double loop electrochemical potentiokinetic reactivation test was carried out to study the degree of sensitization. The effect of different concentrations of chloride ions in 3 M HNO3 at 25 °C indicated tendency for pitting as the concentration of chloride ions was increased. Microstructural examination was carried out by optical microscope and scanning electron microscope after electrolytic etching. X-ray photoelectron spectroscopy study was carried out to investigate the passive film formed in 3 M HNO3 and 3 M HNO3 simulated high level waste. 相似文献
25.
Corrosion fatigue (CF) behaviour of AISI type 316 LN stainless steels (SS) with three different nitrogen contents was evaluated in a boiling aqueous solution of 5?M NaCl+0·15?M Na2SO4+2·5?ml?l?1 HCl at a stress ratio of 0·5 and a frequency of 0·1?Hz. After the CF tests, the specimens were observed under a field emission gun scanning electron microscope (FEG-SEM) as well as an atomic force microscope (AFM) to understand the deformation mechanism which led to the failure. Slip character could be explained based on the surface deformation features observed using FEG-SEM and AFM. A slip irreversibility relation has been proposed which when applied could explain the CF behaviour of these steels with varying nitrogen contents. Increase in the nitrogen content increased the slip reversibility up to 0·14?wt-% nitrogen; however, further increase in nitrogen content had no beneficial effect on the slip reversibility. 相似文献
26.
27.
U. Kamachi Mudali R. K. Dayal J. B. Gnanamoorthy P. Rodriguez 《Metallurgical and Materials Transactions A》1996,27(10):2881-2887
Intergranular corrosion (IGC) resistance of types 304LN and 316LN stainless steels (SS) thermally aged at 823, 873, and 923
K for various durations was assessed by ASTM A262 practice A test (electrolytic etch test) and electrochemical potentiodynamic
reactivation (EPR) test. The results indicated that the type 316LN SS has significantly improved IGC resistance compared to
304LN SS. Based on the results of these tests, time-temperature-sensitization (TTS) diagrams were developed for both alloys.
The secondary precipitates formed during thermal aging treatments were electrochemically extracted and analyzed by X-ray diffraction
(XRD) to determine the types of precipitates formed during the aging treatments. The results indicated that the precipitates
were mostly of M23C6 carbides. 相似文献
28.
N. Parvathavarthini U. Kamachi Mudali Lilyana Nenova Chavdar Andreev Baldev Raj 《Metallurgical and Materials Transactions A》2012,43(6):2069-2084
High nitrogen 304LN stainless steels (SS) intended for chloride and nitric acid environments in spent nuclear fuel reprocessing
and waste management applications were evaluated for their sensitization and intergranular corrosion (IGC) resistance. For
this purpose, high nitrogen (0.132 pct, 0.193 pct and 0.406 pct) containing, impurity-controlled, vanadium-added 304LN SS
alloys were developed. For comparison, 304L SS, which is currently used in reprocessing plants, was also studied. These stainless
steels were subjected to heat treatment at 948 K (675 °C) for various durations ranging from 1 to 1000 hours and tested for
susceptibility to IGC as per ASTM A262 Practice A and E tests. The degree of sensitization was estimated with the double loop
electrochemical potentiokinetic reactivation technique. The increase in nitrogen content resulted in higher hardness and finer
grain size. Based on the detailed microstructural and corrosion studies, it was determined that an addition of 0.132 pct and
0.193 pct nitrogen showed better IGC resistance and an additional increase in nitrogen resulted in deterioration resulting
from chromium nitride precipitation, which was confirmed by electrochemical phase separation and X-ray diffraction studies.
The onset of desensitization was faster for the alloy with 0.132 pct nitrogen as well as 0.406 pct nitrogen because of the
lower nitrogen content in the former case and the finer grain size in the latter case. The higher hardness and superior IGC
resistance of 0.132 pct and 0.193 pct nitrogen containing Type 304LN SS suggests the suitability of this alloy for nitric
acid- and chloride-containing environments of reprocessing and waste management plants. 相似文献
29.
Tantalum and Niobium have good corrosion resistance in nitric acid as well as in molten chloride salt medium encountered in spent fuel nuclear reprocessing plants. Commercially, pure Ti (Cp-Ti) exhibits good corrosion resistance in nitric acid medium; however, in vapor condensates of nitric acid, significant corrosion was observed. In the present study, a thermochemical diffusion method was pursued to coat Ta2O5, Nb2O5, and Ta2O5 + Nb2O5 on Ti to improve the corrosion resistance and enhance the life of critical components in reprocessing plants. The coated samples were characterized by XRD, SEM, EDX, profilometry, micro-scratch test, and ASTM A262 Practice-C test in 65 pct boiling nitric acid. The SEM micrograph of the coated samples showed that uniform dense coating containing Ta2O5 and/or Nb2O5 was formed. XRD patterns indicated the formation of TiO2, Ta2O5/Nb2O5, and mixed oxide/solid solution phase on coated Ti samples. ASTM A262 Practice-C test revealed reproducible outstanding corrosion resistance of Ta2O5-coated sample in comparison to Nb2O5- and Ta2O5 + Nb2O5-coated sample. The hardness of the Ta2O5-coated Cp-Ti sample was found to be twice that of uncoated Cp-Ti. The SEM and XRD results confirmed the presence of protective oxide layer (Ta2O5, rutile TiO2, and mixed phase) on coated sample which improved the corrosion resistance remarkably in boiling liquid phase of nitric acid compared to uncoated Cp-Ti and Ti-5Ta-1.8Nb alloy. Three phase corrosion test conducted on Ta2O5-coated samples in boiling 11.5 M nitric acid showed poor corrosion resistance in vapor and condensate phases of nitric acid due to poor adhesion of the coating. The adhesive strength of the coated samples needs to be optimized in order to improve the corrosion resistance in vapor and condensate phases of nitric acid. 相似文献
30.
Lipika Rani Bairi G. Pannerselvam U. Kamachi Mudali 《Transactions of the Indian Institute of Metals》2012,65(4):333-341
Zirconium present in stainless steel-zirconium metal waste form (MWF) alloys form Ni?CZr and Fe?CZr intermetallic phases which act as a sink for radionuclide and improve resistance to localized corrosion as well as selective radionuclide leaching. The present study looks into the behavior of Zr intermetallics in MWF alloys with the variation of Zr content after heat treatments. Two MWF alloys of D9 SS (Ti modified 15Cr?C15Ni?C2.5Mo stainless steel) with 8.5 and 17?wt% Zr were heat treated at 1,323?K for 2 and 5?h and characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The stability of the Zr intermetallic compounds was examined by high temperature XRD. The results from XRD study showed the presence of NiZr, Ni5Zr, Ni7Zr2, FeZr2, and Fe3Zr peaks along with fcc Fe based solid solution. The MWF alloy with 17?wt% Zr exhibited ??-ferrite peak in as-cast condition which was not observed after heat treatment. From the SEM micrograph the agglomeration of intermetallic phases was observed after heat treatment and the grain size of the intermetallic phases increased with duration of heat treatment. The high temperature XRD study revealed that all the intermetallic phases were stable up to 1,173?K and above this temperature Ni?CZr intermetallics started disappearing. However Fe?CZr intermetallics were stable till 1,373?K. The paper presents the high temperature phase stability of D9 SS-Zr MWF alloys. 相似文献